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Half Wave Rectification Verse Full Wave in an System

Half Wave Rectification Verse Full Wave in an System

Half Wave Rectification Verse Full Wave in an System

(OP)
Can anybody explain the different on what the required power from 3 phase L-L voltage of 115VAC generator using a half or full rectification to a 3KW load?

RE: Half Wave Rectification Verse Full Wave in an System

Well, then power is 3kW so the power doesn't chnage. The way it is drawn from the supply changes, and with half-wave rectification it will all be in one half-cycle repeating at the line frequency, where with full-wave rectification it is drawn in two pulses repeating at double the line frequency.

Half-wave rectification will introduce DC into the machine winding which is almost guaranteed to cause problems because the magnetic core will saturate. Don't do it.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Half Wave Rectification Verse Full Wave in an System

Half is usually not good because it will DC saturate the generator if the load is comparable in size to the generator. Full is better because you will not get a DC component.

Otherwise, I don't mind if it is half full or whatever.

Gunnar Englund
www.gke.org
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Half full - Half empty? I don't mind. It's what in it that counts.

RE: Half Wave Rectification Verse Full Wave in an System

I am not so sure that 3 kW will be drawn at all if you try half-wave rectification.

It is an interesting coincidence that Scotty and I said essentially the same thing at exactly the same time.

Gunnar Englund
www.gke.org
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Half full - Half empty? I don't mind. It's what in it that counts.

RE: Half Wave Rectification Verse Full Wave in an System

Gunnar - I just took the 3kW load at face value - 3kW, regardless of the supply waveform. Probably won't be like that in real life!
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Half Wave Rectification Verse Full Wave in an System

"Great minds think alike." smile

RE: Half Wave Rectification Verse Full Wave in an System

It will depend on what happens after the rectification.  In a classic DC supply, there are capacitors that filter the ripple.  These provide sufficient charge to carry the load through the missing phases, but there will be serious droop during the missing phases.  With full-wave, the droop is the same through all the phases.

TTFN

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